The impact of Sarcopenia on Mortality in Patients with Necrotizing Soft Tissue Infections
Manuel Castillo-Angeles ; Jennifer Uyeda; Elizabeth Bryant; Barbara Okafor; Deepika Nehra; Stephanie Nitzschke; Erika Rangel; Jeffrey Skubic; Matthew Giangola; Ali Salim; Reza Askari
Background:Necrotizing soft-tissue infections (NSTIs) are surgical emergencies associated with high morbidity and mortality. Identifying risk factors for poor outcome is a critical part of preoperative decision-making and counseling. Sarcopenia, the loss of lean muscle mass, has been associated with an increased risk of mortality and can be measured using cross-sectional imaging. Our aim was to determine the impact of sarcopenia on mortality in patients with NSTI.
Hypothesis:We hypothesize that sarcopenia will be associated with an increased risk of mortality in patients with NSTI.
Methods:This is a retrospective cohort study of NSTI patients admitted from 1995 to 2014 to two academic institutions. Average bilateral psoas muscle cross-sectional area at L4, normalized for height (Total Psoas Index [TPI]), was calculated using computed tomography. Sarcopenia was defined as TPI in the lowest sex-specific quartile. Primary outcome was in-hospital mortality. Multivariate logistic regression was performed to assess the association between sarcopenia and in-hospital mortality.
Results:There were 108 patients with preoperative imaging, 62% males and a median age of 58.3 years (IQR 47–68.2). 24 (22%) were immunocompromised. Overall in-hospital mortality was 16%. There was no significant difference in gender, body mass index (BMI), comorbidities and American Society of Anesthesiologists classification (Table 1). Sarcopenic patients were older and had a higher in-hospital mortality rate (p<0.05). After multivariate analysis, sarcopenia was independently associated with increased in-hospital mortality (Odds ratio, 3.5; 95% Confidence Interval [CI], 1.05-11.8).
Conclusions:Sarcopenia is associated with increased risk of in-hospital mortality in patients with Necrotizing soft-tissue infections. Sarcopenia identifies patients with higher likelihood of poor outcomes, which can possibly help surgeons in counseling their patients and families.